A recent study published in New England Journal of Medicine documents for the first time that the use of certain medications used to treat high blood pressure causes a significant risk of children being born with birth defects. The medications in question, Angiotensin-Converting-Enzyme (ACE) inhibitors, have long been contraindicated during the second and third trimesters of pregnancy because of their association with an increased risk of birth defects. This study documents that the use of ACE inhibitors during the first trimester of pregnancy also carries a significant risk of birth defects. The conclusion of the authors of the study is that "Exposure to ACE inhibitors during the first trimester cannot be considered safe and should be avoided." ACE inhibitors which are available in the United States include Captopril (Capoten), Benazepral (Lotensin), Enalapril (Vasotec), Lisinopril (Prinivil), Zestril, Fosinopril (Monopril), Ramipril (Altace), Perindopril (Aceon), Quinapril (Accupril), Moexipril (Univasc) and Trandolapril (Mavik). Patients with high blood pressure who are pregnant should definitely discuss their choice of high blood pressure medications with their doctor in light of this study.